Nail-size extender for gas-actuated nail drivers



Oct. 9, 1956 J. w. WEICHOLD 2,765,454

NAIL-SIZE EXTENDER FOR GAS-ACTUATED NAIL DRIVERS Filed June 16, 1955NAIL-SIZE EXTENDER FOR 'GA S-ACTUATED NAIL DRIVERS Jack WilliamWeichold, Cincinnati,-hio, assignor t0 Chester Tietig, Covington, Ky.

Application June 16, 1955, Serial No. 515,824

6 Claims. (Cl. 1'44.5)

This invention relates to an improvement on a naildriving tool such asis described and shown in U. S. Patent 2,632,890, issued to ChesterTietig.

The object of the present improvement is to provide means to extend therange of sizes of nails that may be driven by the tool without changingthe size or power of the cartridge that is used as the power source.

Another object is to provide this means in a form that is easilyadjusted from one size of nail to another and which is not bulky,cumbersome or diflicult of access.

Briefly stated, the improvement comprises a collar which encircles thecylinder (marked 25 in the patent referred to). The collar is movable toa limited extent along the length of the sleeve 25 to cover or uncover aplurality of exhaust ports (marked 27 in the Tietig patent but herepreferably positioned on the top of the sleeve). The degree ofdi'fiiculty with which the gases from the explosion of the cartridgemake their exit from the ports 27 governs the amount of push given thepiston (marked 28 in the Tietig patent). The more ports which arecovered, the greater the push. Part of the present invention is theprovision of ports which cannot be covered by the collar, thusconstituting a safety measure to insure a sufficient exit for the gasesat all times.

Referring now to the accompanying drawings:

Fig. 1 is a side elevation of the complete tool shown partially in crosssection.

Fig. 2 is an oblique view of the breech portion of the cylinder andcollar. It shows the ports in the sleeve and fragmentary portions of thepiston rod and fore-end.

Fig. 3 is a side elevation of the cylinder with the preferred (screwfastened) form of collar shown in section.

Fig. 4 is a view corresponding to Fig. 3 except that a threaded form ofthe collar is shown and the cylinder is shown in section. In this viewall of the ports are uncovered.

Fig. 5 corresponds to Fig. 4 except that the collar is advanced on itscooperating threads and some of the ports are covered.

In this specification the same numbering of parts as in Patent 2,632,890has been applied wherever possible so that the distinction between theold and the new will be more readily apparent. The improvement howeverresides in the combination with the collar, not the collar per se.

The following matter in quotation marks is quoted from the Tietig patentand constitutes a description of Fig. 1 with the exception of myimprovement. A description of the latter follows the quoted matter. Thisbasic description is necessary so that the improvement may beunderstood. The matter relating to the position of the ports 27 has beenchanged.

In Fig. 1 the firearm shown is a conventional bolt rifle 10, the stock11 of which is shown with its middle portion deleted. In the rifle shown12 is a bolt; 13 is the fore end; 15 is the trigger guard; 16 is thetrigger; 17 is the bolt handle; 18 is a cap for a tubular magazine (notshown); 19 is a blank cartridge in the chamber 20, while 2,765,464Fatented Oct. 9,

21 and 22 are the rear and front receiver rings, the front ring beingadapted to receive the gun barrel 23.

The barrel 23 of my firearm comprises a conventional rearward sectionwhich is provided with a conventional smooth bore 24 preferably of .22cal. The chamber 20 is preferablyof a size to accommodate the .22 longrifle blank cartridge, which will then also accommodate .22 long and .22short blank cartridges.

Threadedly attached to the front portion of the barrel 23 there is acylinder 25 of considerably less wall thickness than that of theconventional barrel 23. On the top of the cylinder 25 at a point a fewinches to the front of the threaded joint 26 between the barrel and thecylinder there are a number of small perforations 27 which are gas andair exhaust ports and also for internal lubrication.

Surrounding the cylinder 25 just forward of the barrel receiver ring 22there is a collar 50 which is rotatably adjustable on the barrel 23either to cover or expose a selected number of the exhaust ports 27 inthe cylinder. Since covering all of the ports 27 might create adangerous condition in the tool owing to the inability of the gases toexhaust, I have provided an auxiliary port or ports 52 "further outalong the cylinder 25 but still close enough to the breech so that thepiston head 28 will pass the port 52 when strongly operated by acartridge. Inasmuch as the length of the collar 50 is so chosen that itis impossible for it to cover ports 27 and 52 simultaneously, port 52constitutes a safety device against blowing up the tool.

In Fig. 2, testing upon the hollowed fore-end 13, just forward=of thefront 'barrel receiver ring 22 and the barrel 23, there is the knurledcollar 56 shown encircling portions of both the barrel 23 and thecylinder 25. Some of the exhaust ports 27 are covered, but the greaternumber of them are shown uncovered. Within the cylinder 25 a sectionedend of the piston rod 23b is visible, together with a short length ofthe rod itself.

In Fig. 3, the preferred form of the collar 50 is shown in sectionhaving a fairly close fit about a fragment of the cylinder 25. A setscrew 51 is provided in the collar 50. The fit of the collar 50 relativeto the cylinder 25 should be free thereby allowing the collar 50 to heslid and rotated, yet not so loose as to fail to obturate most of thegas from the covered holes 27. The set screw may be hand-settable orscrew-driver settable. Indicia (not shown) may be provided on thecylinder 25 to indicate proper positions of the collar for various sizesof cartridges, nails or both. The rest of the construction, i. e. thebreech, may be built as shown and described as follows in regard toFigs. 4 and 5.

In Figs. 4 and 5, the same elements are present as in Figs. 2 and 3,with the addition of a return spring 31 for the piston 28 and its rod281). in Figs. 4 and 5, a thread 53 is provided on the outer surface ofthe barrel 23 or cylinder 25 or both. The inner surface of collar 56) isthreaded to mesh with thread 53 so that by rotating the collar, it maybe advanced or retracted over as many of the ports 27 as may beselected. The fore-end i3 is sufficiently hollowed under the collar toenable the latter to turn freely.

Fig. 4 shows the collar in the retracted position, i. c. with ports 27open. Fig. 5 shows it advanced, i. c. with many of the ports closed.

Fig. 4 shows a modification in which the ports 27 are in the uppersurface of the barrel 23 and that the cylinder 25 is threadedly attachedto the forward end or muzzle of the barrel. In this modification thepiston 28 lies normally in the barrel 23 just ahead of the cartridgechamber, thus economizing length.

In Fig. 5 the barrel 23 and the cylinder 25 are made integral, theexternal thread 26 being common to both so that the collar 50 can holdthem together.

Fig. 3 represents the preferred modification because the collar 50 ismost readily tightened and loosened and because the thread 53 is notnecessary. Fig. 4 is a strong compact construction and Fig. 5 is thestrongest possible, but quite expensive.

Fig. 1 illustrates any of the modifications shown in Figs. 3, 4 and 5.In the matter of Fig. 3 the screw 51 might be dispensed with or mountedon the far side of the collar 50 so that it would not show in Fig. 1.

I claim as my invention:

1. In a gas-actuated nail driver having a nail driving piston, acylinder for the piston having a plurality of gas exhaust ports in aposition slightly forward of the normal resting position of said piston,a collar encircling a substantial part of the circumference of saidcylinder at the area of said ports, said collar being radiallyadjustable and adapted to be advanced or retracted to cover selectivelysaid ports partially or entirely, and means for maintaining the positionof the collar at which it is set, during operation of the nail driver,thereby regulating the number of ports from which gas may beunobstructedly exhausted and obturating the remainder of said ports.

2. In a nail driver of the piston type, a cylinder providing a path forthe actuation of the piston to drive a nail, said cylinder having aplurality of exhaust ports, means encircling said cylinder near saidports comprising an advanceable and retractable cover operable toobstruct substantially the flow of gas, produced by the operation of thenail driver, from a selected number of ports determined by the extent towhich said cover is adjusted, and means for holding the cover in theadjusted position.

3. A gas-actuated nail driving tool comprising, a barrel, a cylinderattached to said barrel, a piston assembly actuable in said cylinder todrive a nail which is positioned on the outer end of said assembly, saidcylinder having a plurality of ports through its walls, said ports beingpositioned a short distance beyond the inner point of rest of the pistonof said piston assembly, and a cover advanceably and retractably held onsaid cylinder whereby to cover a selected number of said ports.

4. A tool according to claim 3 in which the cover is a collar,encircling said cylinder, an internal thread on said collar, and anexternal thread on said cylinder meshing with said internal thread.

5. A tool according to claim 3 in which the cover is a collar encirclingsaid cylinder, and a set-screw in said cylinder whereby the later may belocked upon said cylinder.

6. In a gas-actuated nail driver of the type in which a nail-drivingpiston is contained in a cylinder which i attached to a source of highpressure gas, the improvement which comprises an obturating sleevemounted on the cylinder just forward of the position within the cylinderand of the piston while the latter is at rest, said cylinder beingprovided with a multiplicity of perforations leading to the atmosphere,so proportioned that a substantial portion but not the totality thereofmay be covered by said sleeve to obturate the covered perforations, andmeans for positioning said sleeve adjustably about said cylinderto-obturate a preselected number of perforations.

References Cited in the file of this patent UNITED STATES PATENTS819,834- Zalinski May 8, 1906 2,003,290 Gurney June 4, 1935 2,632,890Tietig Mar. 31, 1953 2,677,823 Magnuson May 11, 1954 FOREIGN PATENTS505,746 Belgium Sept. 29, 1951

